[media] media: add a common struct to be embed on media graph objects

Due to the MC API proposed changes, we'll need to have an unique
object ID for all graph objects, and have some shared fields
that will be common on all media graph objects.

Right now, the only common object is the object ID, but other
fields will be added later on.

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

1 files changed, 32 insertions, 0 deletions

diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
index 0342be39cae2..a76655c2ddef 100644
--- a/drivers/media/media-entity.c
+++ b/drivers/media/media-entity.c
@@ -27,6 +27,38 @@
 #include <media/media-device.h>
 
 /**
+ *  media_gobj_init - Initialize a graph object
+ *
+ * @mdev:	Pointer to the media_device that contains the object
+ * @type:	Type of the object
+ * @gobj:	Pointer to the object
+ *
+ * This routine initializes the embedded struct media_gobj inside a
+ * media graph object. It is called automatically if media_*_create()
+ * calls are used. However, if the object (entity, link, pad, interface)
+ * is embedded on some other object, this function should be called before
+ * registering the object at the media controller.
+ */
+void media_gobj_init(struct media_device *mdev,
+			   enum media_gobj_type type,
+			   struct media_gobj *gobj)
+{
+	/* For now, nothing to do */
+}
+
+/**
+ *  media_gobj_remove - Stop using a graph object on a media device
+ *
+ * @graph_obj:	Pointer to the object
+ *
+ * This should be called at media_device_unregister_*() routines
+ */
+void media_gobj_remove(struct media_gobj *gobj)
+{
+	/* For now, nothing to do */
+}
+
+/**
  * media_entity_init - Initialize a media entity
  *
  * @num_pads: Total number of sink and source pads.